Ventilated floor modular system



3 April 18, 1967 J. V. KNAB VENTILATED FLOQR MODULAR SYSTEM Filed Oct. 18, 1965 3 Sheets-Sheet l 5&6.

INVENTOR. J/IMES 1/. I'M/A5 ATTORNEYS April 18, 1967 J. v. KNAB VENTILATED FLOOR MODULAR SYSTEM Filed on. 18, 1965 3 Sheets-Sheet 2 .M :0 3 e Q. Q

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.INVE'NTOR. z/ X/A/AW ATTORNEYS United States Patent York Filed Oct. 18, 1965, Ser. No. 496,863 11 Claims. (CI. 9831) This invention relates to floor systems and, more particularly, to modular floor systems for use in clean rooms.

Modern electronic manufacturing techniques often require that critical components be assembled and packaged in work areas which have come to be known as clean rooms. Basically, these rooms are enclosures within which temperature and humidity are maintained at desired levels and dust content is kept below prescribed limits. They usually comprise some system for constantly recirculating and processing the air contained within the sealed enclosure.

In clean room construction it is customary to provide one or a plurality of plenum units in the ceiling or walls of the enclosure. A collection chamber is provided he neath the floor or behind one wall of the clean room into which air from the plenum flows after it has passed through the enclosure. A recirculation system is provided for removing the air from the collection chamber, filtering and conditioning it, and recirculating it through the plenum.

The provision of a collection chamber under the floor of a clean room necessitates the utilization of a floor structure which will allow air to flow therethrough into the collection chamber. Current methods for accomplishing this purpose generally provide for cutting away certain portions of the existing floor and fitting prefabricated air flow registers into the cut-away sections. This approach suffers from a number of severe disadvantages. The'register units so installed frequently loosen from the cut-away section in the floor and tend to tip when stepped upon. Furthermore, registers are not sufiiciently strong to carry the heavy loads which often are required to be moved into and out of the clean room enclosure.

In addition to the incapacity of the register sections themselves to carry heavy loads, the cutting away of portions of the floor also weakens the floor itself. If, for example, the floor has been constructed from a plurality of fioor modules there is little bearing surface left within the modules once a section of sufiicient size to receive an air register has been cut away.

Aside from the structural inadequacy of the present mode of clean room floor construction, other disadvantages also exist. For example, the register units frequently catch small objects such as womens shoe heels, there is no unified appearance to the enclosure once it has been completed, and excess air flow frequently occurs in certain locations within the clean room resulting in undesirable whistling.

The present mode of clean room floor construction is extremely expensive both with regard to installation and upkeep. A relatively long construction period is necessary to individually cut and fit each register panel. Once installed, countless hours must be expended to keep the grate units and surrounding floor areas free from dust particles. The clean room floor structures generally in use provide no means for adjusting the air flow capacity of certain or all of the registers short of individually removing and replacing them with different sized grates. In short, the present mode of clean room floor construction restricts the usage of floor collection chambers as air flow cavities and often renders their utilization impractical.

It is an object of this invention to provide a clean is sandwiched between two sheets of metal.

3,3l4,353 Patented Apr. 18, 1967 'ice room fioor structure which does not suffer from the above out-lined disadvantages.

More particularly, it is an object of this invention to provide a floor module for clean room construction which has suificient structural capacity to handle heavy loads without sagging or tearing loose from the floor frame.

It is an object of this invention to provide a floor module for cleanroom construction which may be safely utilized without fear of catching the narrow heels of high heeled shoes or other sharp objects.

It is an object of this invention to provide a floor module for clean room construction which allows a faster erection time and which will endure, after installation, for a longer period of time.

It is an object of this invention to provide a floor module for clean room construction which may be easily cleaned and which Offers a unified appearance to the entire clean room floor.

Finally, it is an object of this invention to provide a floor module for clean room construction which allows adjustment of the air fiow therethrough without removing the modules or any part thereof from the floor support structure.

These and other objects of this invention will 'be readily understood by reference to the following specification and accompanying drawings in which:

FIG. 1 is a partially-broken perspective view of the support structure which forms one section of the floor module which is the subject of this invention;

FIG. 2 is an exploded view of the overall floor module;

.FIG. 3 is a partially-broken cross-sectional view of the floor module showing the assembly details of the air flow adjustment devices of the invention;

FIG. 4 is a perspective view of another embodiment of a damper; v

FIG. 5 is a plan view of an eccentric mechanism associated with the device of FIGS. 1-3;

FIG. 6 is a plan view of a cam mechanism associated with the device of FIG. 4;

FIG. 7 is a partially-broken view showing the pedestals and the means of mounting the floor modules thereon;

FIG. 8 is an elevational schematic view of a clean room embodying the floor modules which are the subject of this invention; and

FIG. 9 is a diagrammatic view illustrating an exemplary mode of assembling the clean room floor structure.

Briefly, this invention comprises a support assembly fabricated from a steel lattice or beehive network which Each of the cover sheets for the support lattice have a plurality of relatively small holes drilled in their peripheries. A perforated damper sheet is positioned adjacent the bottom of the support assembly such that it may be moved along the surface thereof but will not drop away therefrom. The perforations in the damper sheets are identically spaced to those in the bottom of the floor support assembly. Means are provided for selectively positioning the damper sheet such that its perforations match those 'in the bottom of the floor support assembly to such a degree that the desired amount of air may flow through the module structure. I

In one embodiment of this invention the adjustment means comprises a cylindrical bearing member which is mounted within a receiving aperture in the damper sheet. The cylindrical bearing member is eccentrically mounted on a shaft affixed to the floor support assembly. Means are provided whereby the shaft may be rotated, and thus the perforations in the damper sheet selectively matched to those in the floor support assembly from the top of the floor module. In another embodiment of this invention the damper sheet adjustment means comprises a cam are in alignment.

member which is mounted to a shaft supported within the floor support assembly. 'A slot is provided within the damper sheet and the cam, when rotated, pushes the damper sheet first in one direction and then in the opposite direction by engaging and bearing against the sides of the slot.

Referring now to the drawings a preferred embodiment of this invention will be discussed in detail. FIG. 1 is a perspective view of the support assembly which bears the structural loads placed upon the floor modules. The support assembly 1 consists of a load lattice 2 which is preferably formed by welding steel straps in a honeycomb or lattice configuration as shown. Such a configuration is capable of supporting large loads and, yet, does not possess an imperforate surface. Around the load lattice 2 is placed a jacket 3. Jacket 3 functions to insure maintenance of the load bearing configuration of the load lattice 2 and also to provide a relatively smooth surface area on both the top and bottom of the support assembly. Jacket 3 has a series of relatively small upper air perforations 4 and lower air perforations 5 on its opposing surfaces. The sandwich construction of the support assembly shown in FIG. 1 is capable of withstanding relatively large bearing stresses when supported only at the corners while still possessing the capability of allowing air to How therethrough. A plug receiving aperture 6, the purpose of which will become apparent hereinafter, is provided in the bottom of the support assembly 1.

Referring now to FIGS. 2, 3 and 5, the adjustable air damping apparatus which forms a first embodiment of this invention will be described in detail. The upper surface of support assembly 1 is conveniently covered with a finishing sheet 7 having perforations 9 matching perforations 4 in the upper surface of the support assembly. Preferably, finishing sheet 7 takes the form of a section of tile and is lined to the upper surface of support assembly 1 in such a manner that the perforations 4 and 9 To enhance the appearance of the modules and to prevent separation thereof, a series of molding strips 8 may be placed around the edges of finishing sheet 7.

A damper sheet 10, preferably of polyethylene, is placed adjacent the lower surface of support assembly 1. Damp er sheet 10 has a plurality of apertures 11 which are spaced identically to those apertures Sin the bottom of support assembly 1. The damper sheet 10 is held in this position by a plurality of corner supports 29 each of whichhave guide collars 30 and support shoulders 31. The corner supports 29 are passed through support apertures 13 in the damper sheet 10 andf afiixed to the support assembly 1 by means of screws or some other type of well known fastening device. The support apertures 13 are larger than guide collars 30 and thus, in reality, the damper sheet is held in place by support shoulders 31. This allows damper sheet 10 to be moved with respect to support assembly 1 while remaining in relatively close proximity thereto. This movability, of course, necessitates that the guide collars be of slightly greater length than the thickness of the damper sheet.

A plug receiving aperture 6 is provided in the bottom surface of support assembly 1. Generally aligned with plug aperture 6 is an eccentric aperture 12 in the surface of the damper sheet 10. An Allen head stud 23 having a shaft 24 passes through an aperture in hole plug 21, through aperture 12 in damper sheet 10, and into a mating aperture 26 in eccentric 25. Eccentric is provided with a bearing cylinder 27 which fits into the eccentric receiving opening 12 of damper sheet 10. A support shoulder 28 is provided to aid in retaining damper sheet 10 adjacent support assembly 1. As seen best in FIG. 5, aperture 26 in bearing cylinder 27 is off center, preferably being positioned adjacent one edge of the bearing cylinder. The shaft 24 is press fitted into the mating shaft receiving aperture 26 in the eccentric 25. The shaft of stud 23 and the mating aperture 26 are preferably triangular in shape such that a positive fit may be'obtained 4 between the shaft and the eccentric. If extra securing means are deemed advisable, the end of shaft 24 may be keyed or have a screw and washer inserted into the end thereof under shoulder 28.

The damper sheet sub-assembly is then placed adjacent support assembly 1 and the hole plug 21 inserted into hole plug receiving aperture 6 such that the shoulder 22 secure the eccentric mechanism and the damper sheet to the support assembly. The spacing between damper sheet 10 and support assembly 1 has been somewhat exaggerated in FIG. 3 for purposes of clarity. Note that in order for the shoulder of hole plug 21 to effectively lock into support assembly 1 the hole plug receiving aperture 6 must be drilled at an open spot in the load lattice 2. Once the hole plug has been secured to the support assembly the guide collars 34 are attached to support the corners of the damper sheet.

In order to adjust the damper sheet 10, and thus control the amount of air flowing through a particular section or module of flooring, an Allen wrench is passed through an aperture in finishing sheet 7 and into support assembly 1 until it mates with and engages'the Allen head lug 23. As the lugs is rotated the eccentrically mounted bearing cylinder 27 causes each aperture 11 in damper sheet assembly 10 to rotate in a small circle. The support apertures 13 are sufiiciently large to permit this movement. As the damper sheet is rotated the holes or perforations 11 therein approach and recede from completely matching relationship with the perforations 5 in the bottom of support assembly 1 and thus restrict or increase the amount of air flowing through the floor module.

Referring now to FIGS. 4 and 6 of the drawings a second embodiment of the damper adjustment assembly will be described in detail. A damper sheet 70 having a cam slot 43, a series of guide slots 42, and a series of perforations 71 spatially matching those perforations 5 in support assembly 1 is afiixed adjacent support assembly 1 in a manner identical to that described with regard to damper sheet 10. The guide collars mate with guide slots 42 in such a manner as to allow movement in two directions only. A cam mechanism 41 (FIG. 6) is positioned within cam slot 43 in the same manner as shown in FIG. 3. Cam mechanism 41 is provided with a camming surface 46, a support shoulder 44, and a shaft receiving aperture 45 The assembly of the embodiment shown in PR}. 4 and 6 is identical to that described with regard to FIGS. 2, 3 and 5 except that cam mechanism 41 is substituted for eccentric member 27. The same type of lug and shaft may be utilized. As lug 23 is engaged and rotated by the Allen wrench, cam surfaces 46 moves first into abutting relationship with one side of cam slot 43 forcing the damper sheet in longitudinal fashion to one extremity of the cam reach. As rotation is continued cam surface 46 then contacts the opposite side of the cam slot 43 and forces damper sheet 14) in the opposite direction. The guide slots 42 prevent damper 7 0 from moving in all but two directions. It will be apparent that during this process the perforations 71 in damper sheet 79- will intermittently come into and recede from complete alignment with the perforations 5 in the bottom of support assembly 1. This, of course, is utilized to control the amount of air which is allowed to flow through the floor modules.

Referring now to FIG. 7 a system for mounting the floor modules above the enclosure surface will be described. A plurality of pedestals 50 are positioned at predetermined locations within the enclosure. These pedestals have a base 51, an upstanding support member 52 and a planar corner retaining and support plate 53. The corners 54 of the floor modules 55 mate with the corner sections of planar corner retaining and support plates 53 and are thus supported above the floor. Each pedestal supports the corners of fourdifferent modules. It is, of course, necessary at the side of the enclosure. to provide pedestals having only two corner receiving quarters.

Referring now to FIG. 8 the clean room 68 "is shown schematically comprising a plurality of overhead plenum units 60 which may conveniently be manufactured in accordance with the teachings of co-pending application No. 481,249 filed Aug. 20, 1965, and entitled, Filter System. A plurality of these plenum units are connected to a supply duct 61. The plenum units are supported by a grid network of I-beams 62 and 63. Some means such as the seal 64 are necessary to insure that unfiltered air does not leak into the room through the plenum units. A plurality of floor module units 55 are then placed between the pedestals 50 as indicated generally in FIG. 8. The space beneath the fioor modules form an air collection chamber 65 into which the air passes as it flows through the floor modules 55. As is well known in the art, the air from collection chamber 65 is collected in a collection duct 66, reprocessed in a compressor, prefiltering, and conditioning unit 67, and fed back into plenum unit 60 via supply duct 61.

It has been found that it is not necessary to provide an adjustable floor module for each location in the floor of the clean room enclosure. Rather, such floor modules in about half the location in the clean room floor are sufficient to allow the air to pass into the collection chamber without creating undesirable drafts or whistling noises. As shown in FIG. 9, the floor module of this invention is particularly adapted to this situation. The floor module 55 may be interspersed with ordinary floor modules 56. The ordinary floor modules 56 may, for example, take the form of merely a support assembly 1 having a section of unperforated tile and accompanying molding affixed thereto. In this case it is not necessary that any perforation be made within the support assembly.

After the clean room apparatus has been installed the individual floor modules are adjusted to permit the desired degree of air flow therethrough. Note that this invention allows different sections of the room to be adjusted for a different flow rate. Such ability is often desirable when different types of operations or different types of equipment are being utilized at different locations throughout the room. After the desired adjustments 'have been executed the clean room is ready for use.

Thus it will be seen that this invention has provided a floor module for a clean room which may be completely prefabricated before reaching the assembly site. All that is necessary for the workmen to do in assembling the clean room is to position the pedestals and selectively place adjustable flow floor modules and blank floor modules at desired intervals. If necessary, some sort of gasket or ceiling material may be placed between the individual floor modules as they are being installed. This is seldom necessary, however, since there is little tendency for dust particles to flow upward from the collection chamber into the room. The module floor structures are of sufficient strength to bear heavy loads without failing and may .be individually adjusted to provide the prescribed amount of air fiow through any section of the clean room.

While several preferred embodiments of this invention have been described together with minor modifications, it will be recognized that other modifications may be made without departing from the scope and spirit of the invention. Such modifications are to be deemed as included within the scope of the following claims unless these claims, by their language, expressly state otherwise.

What is claimed is:

1. In a clean room having means in the ceiling for supplying filtered and conditioned air, a floor system comprising:

a plurality of pedestals, each said pedestal having a quadratured planar corner retaining and support plate elevated above its base;

a plurality of floor modules suspended between said pedestals such that each support plate supports the corners of four separate modules at least some of said modules having a support assembly with a plurality of upper and lower air apertures in the top and bottom thereof;

a damper sheet with a plurality of damper apertures matching the lower air apertures in said support member;

means for movably mounting said damper sheet adjacent the bottom surface of said support member;

a shaft mounted in said support assembly, said shaft protruding oat of the bottom of said support assembly;

a bearing cylinder eccentrically mounted on said shaft around which is positioned a bearing cylinder receiving aperture in said damper sheet; and

means for rotating said shaft whereby the airflow capacity of said floor module may be adjusted.

2. The combination as set forth in claim 1 wherein said means for rotating said shaft comprises a tool receiving portion afiixed to its upper extremity, said tool receiving portion being generally aligned with one of said upper apertures whereby a tool inserted through said one upper aperture may engage said receiving portion.

3. In a floor module for a clean room adapted to be supported at its peripheral edges and bear floor-loads across its entire surface having a structural core sandwiched between upper and lower generally planar parallel cover sheets, said sheets having a plurality of communicating air apertures therein whereby air can flow through said module, the improvement comprising:

a damper sheet having a plurality of damper apertures matching the air apertures in said lower cover sheet;

means for movably mounting said damper sheet adjacent the bottom surface of said module such that said damper sheet is movable to bring said damper apertures into and out of general registry with said lower air apertures; and

means central the side extremities of said module for adjusting the postion of said damper sheet with respect to said lower cover sheet to selectively register said damper apertures with the apertures in said lower cover sheet whereby the capacity of air fiow through said module may be selectively controlled.

4. The combination as set forth in claim 3 wherein said cone comprises:

a support lattice having a plurality of multi-sided, open faced metallic members afiixed in side by side relationship.

5. In a clean room having means for supplying filtered and conditioned air thereto, an exit surface for said air 0 comprising:

a plurality of apertured panels positioned over said exit surface;

a plurality of damper sheets, each having apertures matching the apertures in each said apertured panel;

means for movably mounting each said damper sheet adjacent one surface of each said apertured panel; and

a shaft mounted in said panel, said shaft protruding out of the back of said panel;

a bearing cylinder eccentrically mounted on said shaft, said bearing cylinder being rotatably encased by a bearing cylinder receiving aperture in said damper sheet; and

means for rotating said shaft whereby the airflow capacity of said panels may be adjusted.

6. In a clean room having means for supplying filtered and conditioned air thereto, an exit surface for said air comprising:

a plurality of apertured panels positioned over said exit surface;

a plurality of damper sheets, each having apertures matching the apertures in each said apertured panel;

means for movably mounting each said damper sheet adjacent one surface of each said apertured panel; and

7 a shaft mounted in said panel, said shaft protruding out of the back (if said panel; a cairi mounted on said shaft; v a slot in said damper sheet within which said cam is positioned; and I means for rotating said shaft whereby the airflow e'a= pacity of said panels may be adjusted. 7. In a clean room having means in the ceiling for supplying filtered and conditioned air, a floor system comprising: V

a plurality of pedestals, each said pedestal having a quadratured planar corner retaining and support plate elevated above its base; a plurality of floor modules suspended between said pedestals such that each support plate supports the corners of four separate modules at least some of said modules having a support assembly with a plurality of upper and lower air apertures in the top and bottom thereof;

a damper sheet with a plurality of damper apertures matching the lower air apertures in said support member;

means for movably mounting said damper sheet adjacent the bottom surface of said support member;

a shaft mounted in said support assembly, said shaft protruding out of the bottom of said support assembly;

a bearing cylinder eccentrically mountedon said shaft around which is positioned a bearing cylinder receiving aperture in said damper sheet; and

means for rotating said shaft whereby the capacity of airflow through said module may be selectively controlled.

8. In a clean room having means in the ceiling for supplying filtered and conditioned air, a floor system comprising:

a plurality of pedestals, each said pedestal having a quadratured planar corner retaining and support plate elevated above its base;

a plurality of floor modules suspended between said pedestals such that each support plate supports the corners of four separate modules at least some of said modules having a support assembly with a plurality of upper and lower air apertures in the top and bottom thereof;

a damper sheet with a plurality of damper apertures matching the lower air apertures in said support member;

means for m-ovably mounting said damper sheet adjacent the bottom surface of said support member;

a shaft mounted in said support assembly, said shaft protruding out of the bottom thereof;

a cam mounted on said shaft;

a slot in said damper sheet within which said cam is positioned; and

means for rotating said shaft whereby the capacity of airflow through said modules may be selectively controlled.

9. A floor module for clean rooms comprising:

a support assembly having a plurality of communicat ing upper and lower air apertures in the top and bottom thereof;

a damper sheet having a plurality of damper apertures matching the lower air apertures in said support member;

means for movably mounting said damper sheet adjacent the bottom surface of said support member; and

a shaft mounted in said support assembly, said shaft protruding out of the bottom thereof;

a cam mounted on said shaft;

a slot in said damper sheet within which said cam is positioned; and

means for rotating said shaft whereby the airflow capacity of said floor module may be adjusted.

10.- In a room having means for supplying filtered and conditioned air thereto and an exit surface for said air at the fioor of said room said exit surface having a plurality of floor modules adapted to be supported at perip'heral extremities thereof and bear floor loads across their entire surface, at least certain of said modules hav ing a structural core sandwiched between upper and lower generally planar parallel cover sheets, said sheets hav ing a plurality of communicating air apertures therein whereby air can fiow therethrough, the improvement comprising:

a plurality of damper sheets having a plurality of damper apertures therein matching the air apertures in said lower cover sheets;

means for movably mounting said damper sheets adjacent the bottom surfaces of said certain modules such that said admper sheets are movable to bring said damper apertures into and out of general re istry with the air apertures in said lower cover sheet; and

means for adjusting the position of said damper sheets with respect to their associated lower cover sheets whereby the capacity of air flow through said certain modules may be selectively controlled.

11. In a room having means for supplying filtered and conditioned air thereto and an exit surface for said air suspended above the floor of said room in generally parallel relationship therewith to form an air collection cavity between said surface and said floor, the improvement in said exit surface comprising:

support and damper members positioned adjacent and slidable With respect to one another, said support member being positioned above said damper member, said support member having a plurality of air apertures therein arranged in a predetermined pattern, said damper member having a plurality of damper apertures therein positioned such that as said damper member is slid with respect to said support member, said damper apertures come into progressively increasing and decreasing registry with said air apertures, said support member being formed of structural material capable of supporting floor loads imposed thereon when supported only at the peripheral edges thereof; and

means for selectively sliding said damper member with respect to said support member.

References Cited by the Examiner UNITED STATES PATENTS 2,251,663 8/1941 Darbo 9841 X 2,576,848 11/1951 Mercier et al. 984l 2,814,242 11/1957 Marini et a1. 98-41 3,200,734 8/1965 Burns et a1. 98-40 3,252,400 5/ 1966 Madl.

ROBERT A. OLEARY, Primary Examiner.

MEYER PERLIN, Examiner.

W. E. WAYNER, Assistant Examiner, 

1. IN A CLEAN ROOM HAVING MEANS IN THE CEILING FOR SUPPLYING FILTERED AND CONDITIONED AIR, A FLOOR SYSTEM COMPRISING: A PLURALITY OF PEDESTALS, EACH SAID PEDESTAL HAVING A QUADRATURED PLANAR CORNER RETAINING AND SUPPORT PLATE ELEVATED ABOVE ITS BASE; A PLURALITY OF FLOOR MODULES SUSPENDED BETWEEN SAID PEDESTALS SUCH THAT EACH SUPPORT PLATE SUPPORTS THE CORNERS OF FOUR SEPARATE MODULES AT LEAST SOME OF SAID MODULES HAVING A SUPPORT ASSEMBLY WITH A PLURALITY OF UPPER AND LOWER AIR APERTURES IN THE TOP AND BOTTOM THEREOF; A DAMPER SHEET WITH A PLURALITY OF DAMPER APERTURES MATCHING THE LOWER AIR APERTURES IN SAID SUPPORT MEMBER; MEANS FOR MOVABLY MOUNTING SAID DAMPER SHEET ADJACENT THE BOTTOM SURFACE OF SAID SUPPORT MEMBER; A SHAFT MOUNTED IN SAID SUPPORT ASSEMBLY, SAID SHAFT PROTRUDING OUT OF THE BOTTOM OF SAID SUPPORT ASSEMBLY; A BEARING CYLINDER ECCENTRICALLY MOUNTED ON SAID SHAFT AROUND WHICH IS POSITIONED A BEARING CYLINDER RECEIVING APERTURE IN SAID DAMPER SHEET; AND MEANS FOR ROTATING SAID SHAFT WHEREBY THE AIRFLOW CAPACITY OF SAID FLOOR MODULE MAY BE ADJUSTED. 